# US 7,670,004 B2 · Dual ZScreen® projection > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,670,004 B2 - Document ID: US7670004B2 - Status: Granted - Kind: B2 - Application number: 11/583,245 - Filed: 2006-10-18 - Published: 2008-06-19 - Granted: 2010-03-02 - Earliest claimed: 2006-10-18 - Assignees: Real D - Inventors: Matt Cowan; Josh Greer; Lenny Lipton - Web page: https://patentgrep.com/patent/US7670004B2 ## CPC - H04N 13/398: Synchronisation thereof; Control thereof - G03B 35/18: by simultaneous viewing - H04N 13/144: for flicker reduction - H04N 13/315: the parallax barriers being time-variant - H04N 13/337: using polarisation multiplexing - H04N 13/341: using temporal multiplexing - H04N 13/363: using image projection screens (volumetric display H04N13/388) - H04N 2213/002: Eyestrain reduction by processing stereoscopic signals or controlling stereoscopic devices - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - G03B: APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR (optical parts of such apparatus G02B; photosensitive materials or processes for photographic purposes G03C; apparatus for processing exposed photographic materials G03D) ## Abstract A system and method for projecting stereoscopic images using a multiple projector arrangement is provided. The design comprises transmitting a first field train from the first projector, the first field train comprising first projector left and right images and concurrently transmitting a second field train from the second projector, the second field train comprising second projector left and right images. The first projector left image is transmitted by the first projector at substantially a same time as the second projector right image is transmitted by the second projector. Alternately, the design comprises transmitting a first field train from the first projector, the first field train comprising first projector left images alternating with first projector right images, and concurrently transmitting a second field train from the second projector, the second field train comprising second projector left images alternating with second projector right images. A quasi-interlacing technique is also provided. ## Claims ### Claim 1 A method for projecting stereoscopic images using a multiple projector arrangement comprising a first projector and a second projector, the method comprising: transmitting a first field train from the first projector, the first field train comprising first projector left and right images; and concurrently transmitting a second field train from the second projector, the second field train comprising second projector right and left images, wherein the first projector left image is transmitted by the first projector at substantially a same time as the second projector right image is transmitted by the second projector. ### Claim 2 (depends on 1) The method of claim 1, wherein the first field train and second field train are free of blank images. ### Claim 3 (depends on 1) The method of claim 1, further wherein the second projector left image is transmitted by the second projector at a later time and substantially a same instance as the first projector right image is transmitted by the first projector. ### Claim 4 (depends on 1) The method of claim 1, further comprising dividing images into first projector left images, first projector right images, second projector left images, and second projector right images, said dividing occurring before said transmitting. ### Claim 5 (depends on 1) The method of claim 1, wherein an observer's left eye perceives one first projector left image transmitted from the first projector followed by a second projector left image transmitted from the second projector. ### Claim 6 (depends on 1) The method of claim 1, further comprising quasi-interlacing the images, wherein quasi-interlacing comprises deconstructing each image by dividing pixels in each image into two sub-images, each sub-image comprising a complementary series of regions comprising fewer pixels than in each image. ### Claim 7 (depends on 6) The method of claim 6, wherein quasi-interlacing comprises transmitting a first sub-image followed by transmitting a complementary second sub-image. ### Claim 8 A method for projecting stereoscopic images using a multiple projector arrangement comprising a first projector and a second projector, the method comprising: transmitting a first field train from the first projector, the first field train comprising first projector left images alternating with first projector right images; concurrently transmitting a second field train from the second projector, the second field train comprising second projector left images alternating with second projector right images; and quasi-interlacing the images; wherein said first projector transmits one first projector left image at a first time substantially identical to the second projector transmitting one second projector left image. ### Claim 9 (depends on 8) The method of claim 8, wherein said first projector transmits one first projector right image at a second time substantially identical to the second projector transmitting one second projector right image. ### Claim 10 (depends on 8) The method of claim 8, wherein when the first projector left image is transmitted from the first projector and the second projector right image is transmitted from the right projector, an observer's right eye does not perceive a significant part of the image. ### Claim 11 (depends on 8) The method of claim 8, wherein the quasi-interlacing comprises deconstructing each image by dividing pixels in each combined image into two sub-images, each sub-image comprising a complementary series of regions comprising fewer pixels than in each image. ### Claim 12 (depends on 11) The method of claim 11, wherein the quasi-interlacing further comprises transmitting a first sub-image followed by transmitting a complementary second sub-image. ### Claim 13 (depends on 8) The method of claim 8, wherein the quasi-interlacing comprises deconstructing the left image and deconstructing the right image by dividing pixels in each of the left and right images into sub-images, each sub-image comprising a complementary series of regions comprising fewer pixels than in each right image and each left image. ### Claim 14 (depends on 13) The method of claim 13, wherein the quasi-interlacing further comprises transmitting a first sub-image followed by transmitting a complementary second sub-image. ### Claim 15 A projection apparatus configured to projecting stereoscopic images, comprising: a first projector configured to transmit a first field train, the first field train comprising first projector left and right images; and a second projector configured to concurrently transmit a second field train, the second field train comprising second projector right and left images, wherein the first projector left image is transmitted by the first projector at substantially a same time as the second projector right image is transmitted by the second projector. ### Claim 16 (depends on 15) The projection apparatus of claim 15, further comprising a connective element between the first projector and the second projector, the connective element configured to enable transmission of synchronization signals between the first projector and the second projector. ### Claim 17 (depends on 15) The projection apparatus of claim 15, wherein the first field train and second field train are free of blank images. ### Claim 18 (depends on 15) The projection apparatus of claim 15, wherein each first projector left image and each first projector right image occurs at least once in alternating succession in the first field train. ### Claim 19 (depends on 15) The projection apparatus of claim 15, further comprising a server arrangement configured to divide images into first projector left images, first projector right images, second projector left images, and second projector right images, and transmit said first projector left images and first projector right images to the first projector, and the second projector left images and second projector right images to the second projector. ### Claim 20 (depends on 15) The projection apparatus of claim 15, wherein an observer's left eye perceives one first projector left image transmitted from the first projector followed by a second projector left image transmitted from the second projector. ### Claim 21 (depends on 19) The projection apparatus of claim 19, wherein the server arrangement is further configured to quasi-interlace the images, wherein quasi-interlacing comprises deconstructing each image by dividing pixels in each image into two sub-images, each sub-image comprising a complementary series of regions comprising fewer pixels than in each image.